1. Field of the Invention
The present invention encompasses a building component used to make insulated concrete forms and, more particularly, a system that can be used to make cast-in-place walls using two opposed side panels or tilt-up walls using a single side panel. The present invention further encompasses components to improve the walls formed and to simplify the construction process.
2. Background Art
Concrete walls in building construction are most often produced by first setting up two parallel form walls and pouring concrete into the space between the forms. After the concrete hardens, the builder then removes the forms, leaving the cured concrete wall.
This prior art technique has drawbacks. Formation of the concrete walls is inefficient because of the time required to erect the forms, wait until the concrete cures, and take down the forms. This prior art technique, therefore, is an expensive, labor-intensive process.
Accordingly, techniques have developed for forming modular concrete walls that use a foam insulating material. The modular form walls are set up parallel to each other and connecting components hold the two form walls in place relative to each other while concrete is poured therebetween. The form walls, however, remain in place after the concrete cures. That is, the form walls, which are constructed of foam insulating material, are a permanent part of the building after the concrete cures. The concrete walls made using this technique can be stacked on top of each other many stories high to form all of a building""s walls. In addition to the efficiency gained by retaining the form walls as part of the permanent structure, the materials of the form walls often provide adequate insulation for the building.
One embodiment of form walls is disclosed in U.S. Pat. No. 5,390,459, which issued to Mensen on Feb. 21, 1995, and which is incorporated herein by reference. This patent discloses xe2x80x9cbridging membersxe2x80x9d that comprise end plates connected by a plurality of web members. The bridging members also use reinforcing ribs, reinforcing webs, reinforcing members extending from the upper edge of the web member to the top side of the end plates, and reinforcing members extending from the lower edge of the web member to the bottom side of the end plates. As one skilled in the art will appreciate, this support system is expensive to construct, which increases the cost of the formed wall. Also, these walls cannot feasibly be used to make floors or roof panels.
The present invention provides an insulated concrete form comprising at least one longitudinally-extending side panel and at least one web member partially disposed within the side panel. The web member extends from adjacent the external surface of the side panel through and out of the interior surface of the side panel. Three embodiments of the present invention that may be used to construct a concrete form are described herein. The first embodiment uses opposed side panels that form a cavity therebetween into which concrete is poured and substantially cured. The second embodiment uses a single side panel as a form, onto which concrete is either poured or below which concrete is poured and the form inserted into. Once the concrete cures and bonds to the side panel in the second embodiment, it is used as a tilt-up wall, floor, or roof panel. The third embodiment operates similar to the first embodiment but, instead of having two opposed side panels to form the cavity, the present invention uses one side panel and an opposed sheet or other form on the opposed side to form the cavity. After the concrete substantially cures in the third embodiment, the sheet can be removed and reused again or, alternatively, remain as part of the formed structure. If the sheet is removed, the resulting structure is similar to a tilt-up wall formed using the second embodiment of the present invention.
In the first embodiment, the web member is preferably partially disposed in the side panel so that a portion of the web member projects beyond the interior surface of the side panel and faces but does not touch an opposing side panel. The first embodiment also uses a connector that attaches to the two web members in opposing side panels, thereby bridging the gap between the two side panels to position the side panels relative to each other. The connectors preferably have apertures to hold horizontally disposed re-bar. The connectors also have different lengths, creating cavities of different widths for forming concrete walls having different thicknesses. The connectors are interchangeable so that the desired width of the wall can be set at the construction site.
For the second embodiment, a portion of the web member preferably projects beyond the interior surface of the side panel. In one design, the side panel is first horizontally disposed so that the interior surface and portion of the web member extending therethrough are positioned upwardly. Forms are placed around the periphery of the side panel and concrete is then poured onto the interior surface. In a second design, the concrete is poured into a volume defined by perimeter forms and then the side panel is placed upon the fluid concrete so that at least a portion of the web member in the side panel is disposed in the concrete. Alternatively, a third design is formed as a hybrid of the first and second designs, namely, one side panel is horizontally disposed, concrete is poured onto the interior surface and contained by forms, and then another panel is place upon the poured concrete so that side panels are on both sides of the concrete. For all three designs, once the concrete substantially cures and bonds with the interior surface of the side panel and the portion of the web member extending therethrough, the side panels and connected concrete slab can be used as a tilt-up wall, flooring member, or roof panel.
The third embodiment of the present invention encompasses a process generally similar to the first embodiment, except that a sheet of plywood or the like is used instead of a second side panel. The sheet can either be removed after the concrete cures and used again or remain part of the formed structure.
The present invention further comprises components to improve the walls formed using side panels and to simplify the construction process.